The sign of the three gilt balls is very common in the Great City, and where the ancient badge of the pawnbroker is not seen, the words "Exchange Office" answer the same purpose. The law recognizes the fact that in all large communities, these dealers are a necessary evil, and while tolerating them as such, endeavors to interpose a safeguard in behalf of the community, by requiring that none but persons of good character and integrity shall exercise the calling.